Question

Help me!

Triangle XYZ is rotated 90° counterclockwise using the origin as the center of rotation.


On a coordinate plane, triangle X Y Z has points (2, 2), (4, 2), (1, negative 1). Triangle X prime Y prime Z prime has points (negative 2, 2), (negative 2, 4), (1, 1).


Which other rotation can be used to create triangle X’Y’Z’ from triangle XYZ?

90° clockwise

270° clockwise

270° counterclockwise

360° counterclockwise

Answer 1

(b) 270° clockwise

Explanation:

You want to know the rotation that is equivalent to 90° CCW.

Rotation

There are 360° in a circle. Any point that can be reached through an angle of θ in the CCW direction can also be reached through an angle of (360°-θ) in the CW direction. 360° -90° = 270°.

The 90° CCW rotation of ∆XYZ to ∆X'Y'Z' is equivalent to a 270° CW rotation, choice B.

<95141404393>